The main objectives of the proposed research are: (1) to develop highly efficient and selective procedures for the preparation of trisubstituted olefins including (a) those which are substituted with one methyl and at least one heterofunctional carbon group and represented by 2 and (b) gamma-ylidenebutenolides based on the Zr-catalyzed carbo-alumination as well as on the Pd- or Ni-catalyzed cross-coupling, and (2) to apply some of such procedures to the synthesis of selected terpenoids, carotenoids, such as vitamin A, and ylidenbutenolides, such as freelingyne.